Department of Neurosurgery and Gamma Knife Radiosurgery, San Raffaele Scientific Institute, Vita-Salute University, Via Olgettina 60, 20132, Milan, Italy.
Acta Neurochir (Wien). 2013 Apr;155(4):619-26. doi: 10.1007/s00701-013-1631-2. Epub 2013 Feb 19.
The reported AVMs obliteration rate after Gamma Knife radiosurgery (GKS) ranges from 70 to 94 %. The objective of the present study was to assess prognostic factors predictive for cerebral AVMs obliteration in 127 patients who underwent GKS.
The AVMs were classified according to the Spetzler-Martin classification. Twenty-one cases (16.5 %) were classified as grade I, 46 cases (36.2 %) as grade II, 51 cases (40.1 %) as grade III, and nine cases (7.1 %) as grade IV-V. The AVMs were deeply located in 16.5 % of patients. The peripheral prescription dose ranged from 16 to 30 Gy (mean 22.3 Gy). The AVMs volume ranged from 0.1 to 13 cc (mean 2.7 cc).
In 72 patients out of the 104 (69.2 %) with a radiological follow-up, MRI showed the AVM obliteration; in 54 cases (60 %) out of the 90 that performed a DSA, a complete AVM obliteration was achieved (average closure time 48.5 months). The volume of the nidus (p = 0.001), the prescription dose (p = 0.004), the 2002 Pollock-Flickinger classification (p = 0.031), and their 2008 revised classification (p = 0.025) were found to be statistically significant in predicting the probability of AVM closure. In the multivariate analysis, only the prescription dose was found to be an independent prognostic factor (p = 0.009) for AVM obliteration.
The volume of the nidus and the prescription dose significantly influence the outcome of radiosurgical treatment. The Pollock-Flickinger classification was found to be a reliable scoring system in predicting the AVM closure and an important tool for selection of patients candidate for GKS.
伽玛刀放射外科治疗（GKS）后报道的动静脉畸形（AVM）闭塞率为 70%至 94%。本研究的目的是评估 127 例接受 GKS 治疗的患者中预测脑 AVM 闭塞的预后因素。
根据 Spetzler-Martin 分类对 AVM 进行分类。21 例（16.5%）为 1 级，46 例（36.2%）为 2 级，51 例（40.1%）为 3 级，9 例（7.1%）为 4-5 级。16.5%的患者 AVM 位置较深。外周处方剂量范围为 16 至 30 Gy（平均 22.3 Gy）。AVM 体积范围为 0.1 至 13 cc（平均 2.7 cc）。
在 104 例有影像学随访的患者中，72 例（69.2%）的 MRI 显示 AVM 闭塞；在 90 例行 DSA 的患者中，54 例（60%）完全闭塞 AVM（平均闭塞时间为 48.5 个月）。病灶体积（p=0.001）、处方剂量（p=0.004）、2002 年 Pollock-Flickinger 分类（p=0.031）及其 2008 年修订分类（p=0.025）均被发现对预测 AVM 闭塞概率具有统计学意义。多因素分析显示，只有处方剂量是 AVM 闭塞的独立预后因素（p=0.009）。
病灶体积和处方剂量显著影响放射外科治疗的结果。Pollock-Flickinger 分类是预测 AVM 闭塞的可靠评分系统，也是选择 GKS 候选患者的重要工具。
